Influence of the Number of Impacts During Incremental Forming on the Mechanical Properties of Copper Wires (2013)

Kuhfuß, B.; Moumi, E.; Bomas, H.; Köhler, B.:

8th International Conference of Micromanufacturing (ICOMM 2013), March 25-28th, 2013, University of Victoria/Canada

Abstract

In incremental forming processes the final geometry is realized in several small forming steps. While for a defined geometry and for a given initial state the total deformation degree is the same, the incremental ones, which relate to the single forming steps, can vary according to the processing parameters. An important question is how the variation of theincremental deformation degree affects the strength of the product after forming. To answer this question at least partially, copper wires with 1.0 mm initial diameter were reduced to 0.5 mm final diameter by infeed rotary swaging. The number of impacts during the process necessary for reaching the end geometry was increased and afterwards tensile tests, microstructure analyses as well as hardness measurements were carried out. It was noted that both hardness and yield strength first increase with the number of forming steps and then, with further increase of this number, decrease against a saturation state. This paper compares own results with such from literature for similar processes and an explanation for the observed behavior is suggested.